1. Technical Field
Aspects of the disclosed subject matter are broadly directed to methods and compositions for producing encapsulated cells and methods of using encapsulated cells, for example, in cellular arrays, screening protocols, and methods of treatment.
2. Related Art
High Throughput Screening (HTS) has been in use for at least the past ten years to screen large numbers of potential chemical compounds that may have pharmaceutical efficacy or which may be precursors to pharmaceuticals. A given investigation may involve the screening of on the order of about 10,000 compounds per day. The screening methods typically involve conducting a chemical reaction in the presence of a test compound to determine the effect of the test compound on the reaction. For example, compounds can be tested for the ability to inhibit or catalyze a desired chemical reaction or enzyme.
Cell based assays are also used in screening assays. With cell based assays, an aliquot of cells is contacted with a test compound to determine whether the test compound produces a desired or expected change in the cells. The test compound producing a change in the cells can be selected for further characterization. Cell based assays have certain advantages over simple chemical reaction assays. In particular, cell based assays can provide more detail on the physiological action of a test compound including, for example, uptake by cells or bioavailability. Unfortunately, cell based assays are not easily incorporated into HTS assays because it is difficult to standardize the number of cells contacted with various test compounds. Without standardizing the number of cells per reaction, meaningful comparisons between compounds are difficult to assess.
Small aliquots of cells having a uniform numbers of cells would facilitate automated manipulation of the cells during HTS. Additionally, such aliquots would be amendable to transplantation into a host using minimally invasive techniques.
Accordingly, there is a need for methods and compositions to produce aliquots of cells having predictable sizes and numbers of cells.